Vinyl derivative and processes of preparing it



Patented Aug. 30, 1932 UNITED STATES PATENT orrlca WALTER E. LAWSON ANDJAMES H. WERRTZ, OF WILMINGTON, DELAWARE, ASSIGNOBS TO E. I. DU PORT DENEMOUBB & COMPANY OF WILMINGTON, DELAWARE, A COB.-

POBA'I'ION OI DELAWARE VINYL DERIVATIVE AND PROCESSES OF PREPARING I! NoDrawing.

This invention relates to the art of polymerization and moreparticularly to a new polymer of vinyl chloride and a process of prearing it.

arious methods have hitherto been developed for the polymerization ofvinyl derivat1ves and these methods resulted in the production of fourdifferent polymers of vinyl chloride,-the alpha polymer, which issoluble in acetone; the beta polymer, which is insoluble in acetone butsoluble in monochlorobenzene; and the delta and gamma pol more, whichare higher polymers substantially insoluble in ordinary solvents. Thesepolymers are all insoluble in aromatic hydrocarbons, thus making itnecessary to use expensive solvents when utilizing these polymers in thepreparation of coating compositions and other commercial products.

We have discovered a new polymer of vinyl chloride, which is soluble inmost aromatic hydrocarbons and in toluene in particular.

It is therefore an object of this invention to provide a new and usefulvinyl chloride polymer.

It is another object of this invention to provide a toluene solublepolymer of vinyl chloride.

It is a further object of this invention to prepare a vinyl chloride poler having lower viscosity characteristics t an previously known polymersof vinyl chloride.

It is a still further object of this invention to provide a process ofmaking a toluene soluble polymer of vinyl chloride.

With the above and other objects in view, which will be apparent as thedescription proceeds, we have set forth our invention in the followingspecification and have included the following examples by way ofillustration and not as a limitation.

In the following examples a solution of vinyl chloride containing thedesired amount of catalyst is forced from a storage c linder through areaction tube by means 0 a gas,

Application Med January 20, 1980. Serial No. 422,215.

such as nitrogen, under ressure or by any other suitable means, sucli asa force pump. The products leaving the reaction tube pass through acoolin coil and are drawn ofi through a careful y regulated needlevalve, the rate of flow through the reaction tube being regulated by therate of draw-oil through this valve.

Example 1 A mixture of 1500 parts by weight of vinyl chloride, 1000parts by weight of toluene, and 45 parts by weight of benzoyl peroxidewas passed through a lead-lined tube 3 feet in length, and having avolume of 463 cc., at a rate of 300 cc. per hour, at 115 to 120 C. undera pressure of 500 lbs. per square inch, furnished by nitrogen gas. 1770parts by weight of light brown solution was obtained. This had an acidnumber of 6.0, a viscosity less than 0.5 poise at 20 C. and contained42.6% solids, which was equivalent to a yield of 50.3% of toluenesoluble polymer of vinyl chloride.

Example 2 A mixture of 2400 parts by weight of vinyl chloride, 1600parts b weight of Hi-flash naphtha, and 96 parts by weight of benzoylperoxide was passed through a lead-lined tube 3 feet in length, andhaving a volume of 463 cc., at a rate of 300 cc. per hour, at atemperature of 110 to 115 C. under a pressure of 500 lbs. per squareinch, furnished y nitro en gas. This gave 3315 parts by weight 0 a whitesolution which had an acid number of 3.8, a viscosity less than 0.5 pose at 20 C. and contained 27.9% solids, which corresponded to a ield of38.3% of toluene soluble polymer of vinyl chloride.

Example 8 A solution conta ning 1500 parts by weight of vinyl chloride,1000 parts by weight of solvent naphtha, and 60 parts by weight ofbenzoyl peroxide was passed through a lead lined tube 1% feet in length,and having a volume of 110 cc., at a rate of 300 cc. per hour, at atemperature of 115 to 120 C. and under a pressure of 500 lbs. per squareinch, furnished by nitrogen gas. This resulted in 1800 parts by weightof a light brown solution which had an acid number of 5.0, and aviscosity of 2.5 poises at 19 C. This contained 42.0% solids, thusgiving a yield of 515% of toluene soluble polymer of vinyl chlo- I'l e.

E sample 4 A mixture of 400 arts by weight of vinyl chloride, 264 partsy weight of ethyl acetate, and 17 parts by weight of benzoyl eroxide waspassed through a lead-line tube 1% feet in length, and having a volumeof 110 cc., at 125 C. under a pressure or 600 lbs. per square inch,furnished by nitrogen gas. The reaction product was 498 parts by weightof an orange colored solution which had a viscosity of less than 0.5poise at 20 0., and contained 34% solids, which corresponded to a yieldof 42.0% of toluene soluble polymer of vinyl chloride.

Example 5 A mixture of 1500 parts by weight of vinyl chloride and 1000parts by Weight of toluene was treated with ozone for a short time (e.g., 1 hour) and then passed through a lead-lined tube 3 feet in length,and havin a volume of 463 cc., at a rate of 300 cc. per our, at 115 to120 C. under a pressure of 500 lbs. per square inch furnished bynitrogen gas. This gave 1330 parts by weight of a white solution whichhad an acid number of 1.0, and a viscosity of less than 0.1 poise at 21C., and contained 13.3% solids, corresponding to a yield of 11.5%toluene soluble polymer of vinyl chloride.

Example 6 A solution containing 87 5 parts by weight of vinyl chloride,575 parts by weight of et'h lene dichloride, and 24 parts by weight ofenzo l peroxide was passed through a lead-line tube 3 feet in length,having a volume of 463 00., at a rate of 400 cc. per hour, at 110 to 120C. under a pressure 01 500 lbs. per square inch, furnished by nitrogengas. There was obtained 930 parts by weight of a brown solution whichhad a viscosity of less than 0.3 poise at 20 C. This contained 26.2%solids, corresponding to a yield of 27.8% of a polymer of vin l chloridewhich was soluble in aromatic hy rocarbons.

Ewample 7' A mixture of 1500 parts by weight of vinyl chloride, 1000parts by weight of acetone, and 45 parts by weight of benzoyl eroxidewas passed through a lead-lined tn 3 feet in length, and having a volumeof 463 cc., at a rate of 300 cc. per hour, at 120 C. under a pressure of500 lbs. per square inch, fur- !ii ed by nitrogen gas. This yielded1742: parts by weight of a light brown solution which had an acid numberof 4.7, and a viscosity of 0.5 poise at 25 C. This contained 45.9%solids, corresponding to a yield of 53.5% of toluene soluble polymer ofvinyl chloride.

E wample 8 A mixture of 2400 parts by weight of vinyl chloride, 1600parts by weight of toluene, and 72 parts by weight of benzoyl peroxidewas passed through a porcelain-lined tube 8 feet in length, and having avolume of approximately 800 cc. at a rate of 1000 cc. per hour, at 105to 110 C. under a pressure of 540 lbs. per square inch, furnished bynitrogen gas. This yielded 2951 art's by weight of a grey coloredsolution Wl'llCll had an acid numer of 4.7, and a viscosity of 0.8 poiseat 21 C. This contained 39.9% solids, corresponding to a yield of 49.1%of toluene soluble polymer of vinyl chloride.

Although the above examples are limited to the use of toluene, Hi-tlashnaphtha and solvent naphtha as examples of aromatic hydrocarbons, toethyl acetate as an example of an ester, to ethylene dichloride as anexample of a halogenated hydrocarbon, and to acetone as an example of aketone, other solvents of these general types, such as xylene, benzeneand monochlorobenzene, may be used.

Furthermore, although we have not found alcohols and ali hatichydrocarbons satisfactor solvents y themselves, we have secured lbwyields of the toluene soluble polymer of vinyl chloride by usingmixtures of aliphatic hydrocarbons with aromatic hydrocarbons, ormixtures of alcohols with aromatic hydrocarbons (for example, usingequal parts of mineral spirits having a boiling point of from 143 to 203C. and Hiflash naphtha, or using equal parts of butyl alcohol andtoluene.) We prefer not to use mixtures of this type, however, becausethe polymer precipitates out after standing a few minutes and thiscauses a clogging of the tubes, with a resultant delay for cleaning,especially if the concentration of vinyl chlo ride is increased.Furthermore, the use of alcohol solvents leads to the formation ofconsiderable quantities of the alpha polymer.

Although benzoyl peroxide and ozone are used as the catalysts in theabove examples, other catalysts, such as other peroxides. includingtoluyl peroxide, palmityl peroxide, acetyl peroxide, hydrogen peroxideand barium peroxide, or an ozonide, can be used.

Likewise, although the above examples are limited to a temperature rangeof from 110 to 125 (1, our process may be carried out at tem eratures offrom 90 to 150 C. We pre er to use a range of 110 to 130 C., however,since polymerization takes place rather slowly at temperatures below 110C. and the polyner darkens at temperatures higher than 130 Although therate at which the reaction mixture is passed through the tubes may bevaried considerably, we prefer to operate under such conditions that thevolume of liquid passing through the tubes per hour has a volume of fromone-half to three times the volume of the reaction tube.

A ressure of at least 200 lbs. per square inch 1s desirable in order tokeep the vinyl chloride in the liquid state, and we prefer to use apressure 0 about 500 lbs. per square inch, particularly with ourpreferred concentration which is a 50 to solution of vinyl chloride inthe solvent used.

Although lead-lined and porcelain reaction tubes are disclosed in theexamples, the lining may be of other suitable material.

The new polymer of vinyl chloride prepared b the process set forthherein not only d fl'ers mm the previously known polymers of vinylchloride in being soluble in aromatic hydrocarbons, whereas none of thepreviously known polymers have been found to be even 5% soluble in suchsolvents, but it is also solublein acetone,chlorobenzene and the othersolvents which dissolve the alpha polymer.

The new polymer also has a far lower viscosity in solution than theother polymers as evidenced by the fact that the alpha polymer, wh ch isthe most soluble one previously described in the literature, forms a gelat room temperature in a 30% concentration in ethyl acetate (one of itsbest solvents), whereas the new polymer has a viscosity of less than 0.5poise under similar circumstances. While we do not Wish to be limited inthis regard, the difference in viscosity characteristics suggests thatthe new polymer is a lower polymer than the alpha form, but attempts toconvert it into the latter form. by subjecting its solutions toultra-violet light or protracted heating in sealed tubes at 100 to 110(3., were unsuccessful.

The new polymer is not readily compatible with drying oils, as shown bythe deposition of cloudy films from solutions conta ning equal Weightsof drying oil and polymer, whereas the alpha polymer is compatible witha considerable number of such oils. Films of the new polymer are slowerdrying, but they are tougher and less brittle than films prepared fromthe alpha polymer.

The new polymer has therefore been found to be a useful ingredient incoating compositions, such as varnishes, enamels and lacquers, and inplastic compositions. Protective finishes prepared from it are unusuallyresistant to moisture, brine and acids, rendering them particularlysuitable for coating objects which come in contact with corrosivematerials.

The new olymer is consequently not only more desira is as a constituentof coating compositions than the tpilreviousl known polymers, but itermits e use 0 cheaper so vents, gives eavier films b reason of thehigher concentrations whi may be employed at spraying viscosities,requires a smaller proportion of softener, and its films retain theirflexibility for much lon er periods than do those of previously ownpolymers. Furthermore, the new polymer e other can be prepared morereadil than t polymers or it is prepared y a continuous process and isnot de endent ulpon sunlight thereof except as defined in the appendedpatent claims.

We claim:

1. A light, colored toluene soluble polymer of vinyl chloride.

2. A synthetic resin which comprises a light colored toluene solublepolymer of vinyl chloride.

3. A polymer of vinyl chloride which has a viscosity of less than 0.5poise in a 30% solution in ethyl acetate at room temperature.

4. The process of making a toluene soluble polymer of vinyl chloride,which comprises passing a mixture containing 1500 parts by weight ofvinyl chloride, 1000 parts b weight of toluene, and 45 parts by weight 0benzoyl peroxide through a reaction tube having a capacity of from 450to 500 parts by Weight of the reaction mixture at a rate of 200 to 600parts per hour at a temperature of 115 to 120 C. and under a pressure of500 lbs. per square inch.

5. The process of securing a yield of toluene soluble polymer of vinylchloride in excess of a 25% conversion, which comprises passing amixture of vinyl chloride, toluene and benzoyl peroxide through areaction tube at a temperature of 110 to 120 C., and under a pressure ofabout 500 lbs. per square inch.

6. The method of making a toluene-soluble polymer of vinyl chloridewhich comprises polymerlzing a vinyl chloride solution by passing thesolution through a polymerizing tube heated to a temperature between 90and 150 C. at a rate such that the volume of solution passed through thetube in one hour is from one-half to three times the volume of the tubeat a pressure above atmospheric and with continuous withdrawl of thepolymer.

7. The method of making a toluene-soluble polymer of vinyl chloridecomprising polymerizing a vinyl chloride solution containing a thpolymerization catalyst and solvents other an alcohols and aliphatichydrocarbons by passing the solution through a olymerizing tube heatedto a temperature etween 110 kee wit the vinyl chloride in a li uid stateand continuous withdrawal 0, the polymer. 8. The method of making atoluene-soluble polymer of vinyl chloride comprising polymerizing avinyl chloride solution containing heated to a temperatureoxygen-containin olymerization catalyst and a solvent containing tolueneby passing e solution through a p'olymerizing tube etween 110 and 130 C.at a rate such that the volume of solution passed through the tube inone hour from one-half to three times the volume the tube at a pressuregreater than 200 lbs.

per sq. in. and with continuous withdrawal the polymer. 9. The methodset forth in claim 8 in which e pressure is about 500 lbs. per sq. in.

In testimony where we afiix our signatures.

WALTER E. LAWSON. JAMES H. WERNTZ.

CERTIFICATE OF CORRECTION.

Patent No. 1,874,107. August 30, 1932.

WALTER E. LAWSON ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 3,line 95, claim 1, after the word "light" strike out the comma; and thatthe said Letters Patout should be read with this correction therein thatthe same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of November, A. D. 1932.

M. J. Moore,

(Seal) Acting Commissioner of Patents.

pheric and with continuous withdrawl of the polymer.

7. The method of making a toluene-soluble polymer of vinyl chloridecomprising polymerizing a vinyl chloride solution containing a thpolymerization catalyst and solvents other an alcohols and aliphatichydrocarbons by passing the solution through a olymerizing tube heatedto a temperature etween 110 kee wit the vinyl chloride in a li uid stateand continuous withdrawal 0, the polymer. 8. The method of making atoluene-soluble polymer of vinyl chloride comprising polymerizing avinyl chloride solution containing heated to a temperatureoxygen-containin olymerization catalyst and a solvent containing tolueneby passing e solution through a p'olymerizing tube etween 110 and 130 C.at a rate such that the volume of solution passed through the tube inone hour from one-half to three times the volume the tube at a pressuregreater than 200 lbs.

per sq. in. and with continuous withdrawal the polymer. 9. The methodset forth in claim 8 in which e pressure is about 500 lbs. per sq. in.

In testimony where we afiix our signatures.

WALTER E. LAWSON. JAMES H. WERNTZ.

CERTIFICATE OF CORRECTION.

Patent No. 1,874,107. August 30, 1932.

WALTER E. LAWSON ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 3,line 95, claim 1, after the word "light" strike out the comma; and thatthe said Letters Patout should be read with this correction therein thatthe same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of November, A. D. 1932.

M. J. Moore,

(Seal) Acting Commissioner of Patents.

